| Aenigmephemeridae Tshernova, 1968 | | 1 | Species | Taxom |
| Ameletidae McCafferty, 1991 | Combmouthed Minnow Mayflies | 2 | Species | Taxom |
| Ameletopsidae Edmunds, 1957 | | 1 | Species | Taxom |
| Ametropodidae Bengtsson, 1913 | Sand minnow mayflies | 3 | Species | Taxom |
| Arthropleidae Balthasar, 1937 | Flatheaded Mayflies | 3 | Species | Taxom |
| Australiphemeridae McCafferty, 1991 | | 2 | Species | Taxom |
| Babidae Kluge, Godun..., 2006 | | 1 | Species | Taxom |
| Baetidae Leach, 1815 | Mayflies | 285 | Species | Taxom |
| Baetiscidae Banks, 1900 | Armored Mayflies | 5 | Species | Taxom |
| Behningiidae Motas & Bacesco, 1937 | Tuskless burrowing mayflies | 1 | Species | Taxom |
| Bojophlebiidae Kukalova-Peck, 1985 | | 1 | Species | Taxom |
| Caenidae Newman, 1853 | Small square-gill mayflies | 70 | Species | Taxom |
| Coloburiscidae Edmunds, 1963 | | 1 | Species | Taxom |
| Ecdyoneuridae | | 2 | Species | Taxom |
| Epeoromimidae Tshernova, 1969 | | 1 | Species | Taxom |
| Ephemerellidae (Klapálek, 1909) | Blue-Winged Olive Ephemerellidae | 134 | Species | Taxom |
| Ephemeridae Leach, 1817 | Burrowing mayflies | 53 | Species | Taxom |
| Euthyplociidae Lestage, 1921 | | 2 | Species | Taxom |
| Fuyoidae Zhang & Kluge, 2007 | | 1 | Species | Taxom |
| Heptageniidae Needham, 1901 | Flat-Bodied Up-Wings Heptageniidae | 329 | Species | Taxom |
| Hexagenitidae Lameere, 1917 | | 22 | Species | Taxom |
| Jarmilidae Demoulin, 1970 | | 5 | Species | Taxom |
| Leptohyphidae Landa & Soldán, 1985 | Little Stout Crawler Mayflies | 5 | Species | Taxom |
| Leptophlebiidae Banks, 1900 | Leptophlebiids | 174 | Species | Taxom |
| Lithoneuridae Sroka & al., 2014 | | 1 | Species | Taxom |
| Litophlebiidae Hubbard & Riek, 1978 | | 1 | Species | Taxom |
| Mesephemeridae Lameere, 1917 | | 6 | Species | Taxom |
| Mesoplectopteridae Demoulin, 1955 | | 1 | Species | Taxom |
| Misthodotidae Tillyard, 1932 | | 7 | Species | Taxom |
| Neoephemeridae Traver, 1935 | Large square-gilled mayflies | 6 | Species | Taxom |
| Nesameletidae (Kluge, Stude..., 1995) | | 1 | Species | Taxom |
| Oligoneuriidae Ulmer, 1914 | Brushleg Mayflies | 44 | Species | Taxom |
| Palingeniidae Albarda, 1888 | Riverbed Burrower Mayflies | 8 | Species | Taxom |
| Polymitarcyidae Banks, 1900 | Pale Burrower Mayflies | 26 | Species | Taxom |
| Potamanthidae Albarda, 1888 | Hacklegill mayflies | 25 | Species | Taxom |
| Prosopistomatidae Lameere, 1917 | | 26 | Species | Taxom |
| Protereismatidae Lameere, 1917 | | 15 | Species | Taxom |
| Sharephemeridae Sinitshenkova, 2002 | | 3 | Species | Taxom |
| Siphlonuridae Banks, 1900 | Primitive Minnow Mayflies | 94 | Species | Taxom |
| Syntonopteridae Handlirsch, 1911 | | 1 | Species | Taxom |
| Tintorinidae Krzeminski &..., 2001 | | 1 | Species | Taxom |
| Torephemeridae Sinitshekova, 1989 | | 4 | Species | Taxom |
| Toxodotidae Sinitshenkov..., 2005 | | 1 | Species | Taxom |
| Triassoephemeridae Sinitshenkov..., 2005 | | 1 | Species | Taxom |
| Triassomanthidae Sinitshenkov..., 2005 | | 1 | Species | Taxom |
| Tricorythidae Lestage, 1942 | Little stout crawler mayflies | 6 | Species | Taxom |
| Triplosobidae Handlirsch, 1906 | | 1 | Species | Taxom |
| Vogesonymphidae Sinitshenkov..., 2005 | | 3 | Species | Taxom |
| Voltziaephemeridae Sinitshenkov..., 2005 | | 1 | Species | Taxom |
